Question

Q)the nature of oxide formed by sulphur?

Answer 1

oxides of sulpher are SO2 & SO3 both are acidic 
as SO2 + H2O ----------------> H2SO3 { sulfurous acid } 
SO3 + H2O--------------------------> H2SO4 { sulfuric acid }

Answer 2

Sulphur oxide is acidic in nature because almost all non-metal oxides are acidic in nature.We can too verify it by reacting it with water, testing with litmus ,etc.